Characterization of a novel low-molecular-mass dual specificity phosphatase-4 (LDP-4) expressed in brain

Mol Cell Biochem. 2007 Feb;296(1-2):177-84. doi: 10.1007/s11010-006-9313-5. Epub 2006 Sep 26.

Abstract

Dual-specificity phosphatases (DSPs), which dephosphorylate proteins at Ser/Thr as well as Tyr residues, are thought to be involved in critical signaling events such as control of MAP kinases (MAPKs). We have isolated the cDNA for a novel DSP and termed it low molecular mass DSP-4 (LDP-4). LDP-4 is composed of 211 amino acids with a predicted molecular mass of 23.9-kDa. Northern blot analysis using various mouse tissues showed that the LDP-4 transcript was expressed exclusively in brain. In situ hybridization showed that brain expression of LDP-4 was ubiquitous except for the hippocampus. When expressed in COS-7 cells, FLAG-tagged LDP-4 protein was present within the nucleus and Golgi apparatus. LDP-4 expression did not reduce phosphorylation levels of MAPKs, but rather evoked activation of JNK and p38.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Brain / anatomy & histology
  • Brain / metabolism*
  • COS Cells
  • Chlorocebus aethiops
  • Enzyme Activation
  • Humans
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Mice
  • Molecular Sequence Data
  • Molecular Weight
  • Nerve Tissue Proteins / chemistry
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Phosphoric Monoester Hydrolases / chemistry
  • Phosphoric Monoester Hydrolases / genetics
  • Phosphoric Monoester Hydrolases / metabolism*
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Tissue Distribution
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Nerve Tissue Proteins
  • JNK Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • LDP-4 protein, mouse
  • Phosphoric Monoester Hydrolases